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Honda K. Peripheral regulation of food intake in chickens: adiposity signals, satiety signals and others. WORLD POULTRY SCI J 2021. [DOI: 10.1080/00439339.2021.1898296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- K. Honda
- Graduate School of Agricultural Science, Kobe University, Kobe, Japan
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El-Salhy M, Hatlebakk JG, Hausken T. Possible role of peptide YY (PYY) in the pathophysiology of irritable bowel syndrome (IBS). Neuropeptides 2020; 79:101973. [PMID: 31727345 DOI: 10.1016/j.npep.2019.101973] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/15/2019] [Accepted: 09/18/2019] [Indexed: 12/19/2022]
Abstract
Irritable bowel syndrome (IBS) is a common gastrointestinal disorder of unknown aetiology for which there is no effective treatment. Although IBS does not increase mortality, it reduces the quality of life and is an economic burden to both the patients themselves and society as a whole. Peptide YY (PYY) is localized in endocrine cells located in the ileum, colon and rectum. The concentration of PYY and the density of PYY cells are decreased in both the colon and rectum but unchanged in the ileum of patients with IBS. The low density of PYY cells in the large intestine may be caused by a decreased number of stem cells and their progeny toward endocrine cells. PYY regulates the intestinal motility, secretion and absorption as well as visceral sensitivity via modulating serotonin release. An abnormality in PYY may therefore contribute to the intestinal dysmotility and visceral hypersensitivity seen in IBS patients. Diet management involving consuming a low-FODMAP diet restores the density of PYY cells in the large intestine and improves abdominal symptoms in patients with IBS. This review shows that diet management appears to be a valuable tool for correcting the PYY abnormalities in the large intestine of IBS patients in the clinic.
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Affiliation(s)
- Magdy El-Salhy
- Section for Gastroenterology, Department of Medicine, Stord Hospital, Stord, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Bergen, Norway..
| | - Jan Gunnar Hatlebakk
- Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Bergen, Norway..
| | - Trygve Hausken
- Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Bergen, Norway..
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Comeras LB, Herzog H, Tasan RO. Neuropeptides at the crossroad of fear and hunger: a special focus on neuropeptide Y. Ann N Y Acad Sci 2019; 1455:59-80. [PMID: 31271235 PMCID: PMC6899945 DOI: 10.1111/nyas.14179] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 05/15/2019] [Accepted: 06/03/2019] [Indexed: 12/11/2022]
Abstract
Survival in a natural environment forces an individual into constantly adapting purposive behavior. Specified interoceptive neurons monitor metabolic and physiological balance and activate dedicated brain circuits to satisfy essential needs, such as hunger, thirst, thermoregulation, fear, or anxiety. Neuropeptides are multifaceted, central components within such life‐sustaining programs. For instance, nutritional depletion results in a drop in glucose levels, release of hormones, and activation of hypothalamic and brainstem neurons. These neurons, in turn, release several neuropeptides that increase food‐seeking behavior and promote food intake. Similarly, internal and external threats activate neuronal pathways of avoidance and defensive behavior. Interestingly, specific nuclei of the hypothalamus and extended amygdala are activated by both hunger and fear. Here, we introduce the relevant neuropeptides and describe their function in feeding and emotional‐affective behaviors. We further highlight specific pathways and microcircuits, where neuropeptides may interact to identify prevailing homeostatic needs and direct respective compensatory behaviors. A specific focus will be on neuropeptide Y, since it is known for its pivotal role in metabolic and emotional pathways. We hypothesize that the orexigenic and anorexigenic properties of specific neuropeptides are related to their ability to inhibit fear and anxiety.
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Affiliation(s)
- Lucas B Comeras
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
| | - Herbert Herzog
- Neuroscience Division, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
| | - Ramon O Tasan
- Department of Pharmacology, Medical University Innsbruck, Innsbruck, Austria
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Honda K, Saneyasu T, Kamisoyama H. Gut Hormones and Regulation of Food Intake in Birds. J Poult Sci 2017; 54:103-110. [PMID: 32908415 PMCID: PMC7477125 DOI: 10.2141/jpsa.0160100] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 11/02/2016] [Indexed: 02/07/2023] Open
Abstract
Gut hormones act as appetite regulatory hormones in mammals. For example, the hunger hormone ghrelin, which is released from the stomach before food intake, stimulates appetite. In contrast, satiety hormones such as cholecystokinin, glucagon-like peptide-1, and peptide YY, which are released from the intestines after food intake, suppress appetite. The effects of these peptides on food intake have been shown to be similar in both mammals and fishes. However, evidence suggests that the physiological roles of these gut hormones may be different between birds and other vertebrates. This review summarizes the current information on the roles of gut hormones in the regulation of food intake in birds, especially in chickens.
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Affiliation(s)
- Kazuhisa Honda
- Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
| | - Takaoki Saneyasu
- Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
| | - Hiroshi Kamisoyama
- Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
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Aoki K, Kondo M, Okuda M, Saneyasu T, Honda K, Kamisoyama H. Identification, expression analysis, and functional characterization of peptide YY in chickens (Gallus gallus domesticus). Gen Comp Endocrinol 2017; 242:11-17. [PMID: 27118705 DOI: 10.1016/j.ygcen.2016.04.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 04/05/2016] [Accepted: 04/22/2016] [Indexed: 01/04/2023]
Abstract
Peptide YY (PYY) functions as a postprandial satiety signal in mammals. However, the genomic information and physiological roles of chicken PYY have not yet been clarified, although PYY peptide was isolated from chicken intestines in 1992. In this study, we identified a full-length complementary DNA (cDNA) sequence encoding the chicken PYY precursor. The deduced amino acid sequence of chicken PYY was completely consistent with the previously identified peptide sequence. PYY mRNA was abundantly expressed in the small intestine compared with the large intestine. PYY mRNA levels in the jejunum were significantly higher during ad libitum feeding compared with fasting, suggesting that intestinal PYY expression is altered in response to nutritional status in chicks. Intravenous administration of PYY significantly suppressed food intake in chicks. Furthermore, neuropeptide Y receptor Y2, a possible target of PYY, was expressed in various brain regions including the appetite-regulating centers in chicks. This is the first evidence that the intestinal hormone PYY may function as an anorexigenic hormone in chicks.
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Affiliation(s)
- Koji Aoki
- Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
| | - Makoto Kondo
- Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
| | - Mika Okuda
- Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
| | - Takaoki Saneyasu
- Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
| | - Kazuhisa Honda
- Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan.
| | - Hiroshi Kamisoyama
- Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
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Tasan RO, Verma D, Wood J, Lach G, Hörmer B, de Lima TCM, Herzog H, Sperk G. The role of Neuropeptide Y in fear conditioning and extinction. Neuropeptides 2016; 55:111-26. [PMID: 26444585 DOI: 10.1016/j.npep.2015.09.007] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 09/10/2015] [Accepted: 09/10/2015] [Indexed: 12/23/2022]
Abstract
While anxiety disorders are the brain disorders with the highest prevalence and constitute a major burden for society, a considerable number of affected people are still treated insufficiently. Thus, in an attempt to identify potential new anxiolytic drug targets, neuropeptides have gained considerable attention in recent years. Compared to classical neurotransmitters they often have a regionally restricted distribution and may bind to several distinct receptor subtypes. Neuropeptide Y (NPY) is a highly conserved neuropeptide that is specifically concentrated in limbic brain areas and signals via at least 5 different G-protein-coupled receptors. It is involved in a variety of physiological processes including the modulation of emotional-affective behaviors. An anxiolytic and stress-reducing property of NPY is supported by many preclinical studies. Whether NPY may also interact with processing of learned fear and fear extinction is comparatively unknown. However, this has considerable relevance since pathological, inappropriate and generalized fear expression and impaired fear extinction are hallmarks of human post-traumatic stress disorder and a major reason for its treatment-resistance. Recent evidence from different laboratories emphasizes a fear-reducing role of NPY, predominantly mediated by exogenous NPY acting on Y1 receptors. Since a reduction of fear expression was also observed in Y1 receptor knockout mice, other Y receptors may be equally important. By acting on Y2 receptors, NPY promotes fear extinction and generates a long-term suppression of fear, two important preconditions that could support cognitive behavioral therapies in human patients. A similar effect has been demonstrated for the closely related pancreatic polypeptide (PP) when acting on Y4 receptors. Preliminary evidence suggests that NPY modulates fear in particular by activation of Y1 and Y2 receptors in the basolateral and central amygdala, respectively. In the basolateral amygdala, NPY signaling activates inhibitory G protein-coupled inwardly-rectifying potassium channels or suppresses hyperpolarization-induced I(h) currents in a Y1 receptor-dependent fashion, favoring a general suppression of neuronal activity. A more complex situation has been described for the central extended amygdala, where NPY reduces the frequency of inhibitory and excitatory postsynaptic currents. In particular the inhibition of long-range central amygdala output neurons may result in a Y2 receptor-dependent suppression of fear. The role of NPY in processes of learned fear and fear extinction is, however, only beginning to emerge, and multiple questions regarding the relevance of endogenous NPY and different receptor subtypes remain elusive. Y2 receptors may be of particular interest for future studies, since they are the most prominent Y receptor subtype in the human brain and thus among the most promising therapeutic drug targets when translating preclinical evidence to potential new therapies for human anxiety disorders.
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Affiliation(s)
- R O Tasan
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria.
| | - D Verma
- Institute of Physiology I, University of Münster, D-48149 Münster, Germany
| | - J Wood
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - G Lach
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria; Capes Foundation, Ministry of Education of Brazil, 70040-020 Brasília/DF, Brazil
| | - B Hörmer
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - T C M de Lima
- Department of Pharmacology, Federal University of Santa Catarina, 88049-970 Florianópolis, Brazil
| | - H Herzog
- Neuroscience Research Program, Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
| | - G Sperk
- Department of Pharmacology, Medical University Innsbruck, 6020 Innsbruck, Austria
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El-Salhy M, Hausken T. The role of the neuropeptide Y (NPY) family in the pathophysiology of inflammatory bowel disease (IBD). Neuropeptides 2016; 55:137-44. [PMID: 26431932 DOI: 10.1016/j.npep.2015.09.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 09/11/2015] [Accepted: 09/15/2015] [Indexed: 12/15/2022]
Abstract
Inflammatory bowel disease (IBD) includes three main disorders: ulcerative colitis, Crohn's disease, and microscopic colitis. The etiology of IBD is unknown and the current treatments are not completely satisfactory. Interactions between the gut neurohormones and the immune system are thought to play a pivot role in inflammation, especially in IBD. These neurohormones are believed to include members of the neuropeptide YY (NPY) family, which comprises NPY, peptide YY (PYY), and pancreatic polypeptide (PP). Understanding the role of these peptides may shed light on the pathophysiology of IBD and potentially yield an effective treatment tool. Intestinal NPY, PYY, and PP are abnormal in both patients with IBD and animal models of human IBD. The abnormality in NPY appears to be primarily caused by an interaction between immune cells and the NPY neurons in the enteric nervous system; the abnormalities in PYY and PP appear to be secondary to the changes caused by the abnormalities in other gut neurohormonal peptides/amines that occur during inflammation. NPY is the member of the NPY family that can be targeted in order to decrease the inflammation present in IBD.
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Affiliation(s)
- Magdy El-Salhy
- Section for Gastroenterology, Department of Medicine, Stord Hospital, Stord, Norway; Section for Neuroendocrine Gastroenterology, Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Department of Medicine, Haukeland University Hospital, Bergen, Norway.
| | - Trygve Hausken
- Section for Neuroendocrine Gastroenterology, Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway; National Centre for Functional Gastrointestinal Disorders, Department of Medicine, Haukeland University Hospital, Bergen, Norway.
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El-Salhy M, Mazzawi T, Gundersen D, Hatlebakk JG, Hausken T. The role of peptide YY in gastrointestinal diseases and disorders (review). Int J Mol Med 2013; 31:275-82. [PMID: 23292145 PMCID: PMC4042877 DOI: 10.3892/ijmm.2012.1222] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 11/09/2012] [Indexed: 12/13/2022] Open
Abstract
Peptide YY (PYY) is affected in several gastrointestinal diseases and disorders. Changes in PYY appear to be an adaptive response to alterations in pathophysiological conditions caused by the disease. This applies to gastrointestinal diseases/disorders such as irritable bowel syndrome, inflammatory bowel disease, celiac disease, systemic sclerosis, and post-intestinal resection. By contrast, the changes in PYY in chronic idiopathic slow transit constipation (CST) seem to be of a primary nature, and may be one etiological factor of the disease. Abnormalities in PYY seem to contribute to the development of symptoms present in irritable bowel syndrome, inflammatory bowel disease, gastroenteropathy in long-standing diabetes and CST. The changes in PYY could, however, be favorable in some gastrointestinal disorders such as celiac disease, systemic sclerosis and post-intestinal resection state. Investigating changes in PYY in gastrointestinal diseases/disorders could be beneficial in clinical practice, where a receptor agonist or an antagonist can be used as a drug, depending on the condition. Similar to other neuroendocrine peptides/amines of the gut, PYY has broad physiological/pharmacological effects: it can bind to and activate several receptors with independent actions. Thus, in order to use PYY as a drug, receptor-specific agonists or antagonists need to be developed.
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Affiliation(s)
- Magdy El-Salhy
- Section for Gastroenterology, Department of Medicine, Stord Helse-Fonna Hospital, Stord, Norway.
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Martin GR, Beck PL, Sigalet DL. Gut hormones, and short bowel syndrome: The enigmatic role of glucagon-like peptide-2 in the regulation of intestinal adaptation. World J Gastroenterol 2006; 12:4117-29. [PMID: 16830359 PMCID: PMC4087358 DOI: 10.3748/wjg.v12.i26.4117] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Short bowel syndrome (SBS) refers to the malabsorption of nutrients, water, and essential vitamins as a result of disease or surgical removal of parts of the small intestine. The most common reasons for removing part of the small intestine are due to surgical intervention for the treatment of either Crohn's disease or necrotizing enterocolitis. Intestinal adaptation following resection may take weeks to months to be achieved, thus nutritional support requires a variety of therapeutic measures, which include parenteral nutrition. Improper nutrition management can leave the SBS patient malnourished and/or dehydrated, which can be life threatening. The development of therapeutic strategies that reduce both the complications and medical costs associated with SBS/long-term parenteral nutrition while enhancing the intestinal adaptive response would be valuable.
Currently, therapeutic options available for the treatment of SBS are limited. There are many potential stimulators of intestinal adaptation including peptide hormones, growth factors, and neuronally-derived components. Glucagon-like peptide-2 (GLP-2) is one potential treatment for gastrointestinal disorders associated with insufficient mucosal function. A significant body of evidence demonstrates that GLP-2 is a trophic hormone that plays an important role in controlling intestinal adaptation. Recent data from clinical trials demonstrate that GLP-2 is safe, well-tolerated, and promotes intestinal growth in SBS patients. However, the mechanism of action and the localization of the glucagon-like peptide-2 receptor (GLP-2R) remains an enigma. This review summarizes the role of a number of mucosal-derived factors that might be involved with intestinal adaptation processes; however, this discussion primarily examines the physiology, mechanism of action, and utility of GLP-2 in the regulation of intestinal mucosal growth.
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Affiliation(s)
- G-R Martin
- Department of Gastrointestinal Sciences, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW., Calgary, Alberta T2N 4N1, Canada.
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Abstract
Neuropeptide Y (NPY), peptide YY (PYY) and pancreatic polypeptide (PP) belong to the NPY hormone family and activate a class of receptors called the Y-receptors, and also belong to the large superfamily of the G-protein coupled receptors. Structure-affinity and structure-activity relationship studies of peptide analogs, combined with studies based on site-directed mutagenesis and anti-receptor antibodies, have given insight into the individual characterization of each receptor subtype relative to its interaction with the ligand, as well as to its biological function. A number of selective antagonists at the Y1-receptor are available whose structures resemble that of the C-terminus of NPY. Some of these compounds, like BIBP3226, BIBO3304 and GW1229, have recently been used for in vivo investigations of the NPY-induced increase in food intake. Y2-receptor selective agonists are the analog cyclo-(28/32)-Ac-[Lys28-Glu32]-(25-36)-pNPY and the TASP molecule containing two units of the NPY segment 21-36. Now the first antagonist with nanomolar affinity for the Y2-receptor is also known, BIIE0246. So far, the native peptide PP has been shown to be the most potent ligand at the Y4-receptor. However, by the design of PP/NPY chimera, some analogs have been found that bind not only to the Y4-, but also to the Y5-receptor with subnanomolar affinities, and are as potent as NPY at the Y1-receptor. For the characterization of the Y5-receptor in vitro and in vivo, a new class of highly selective agonists is now available. This consists of analogs of NPY and of PP/NPY chimera which all contain the motif Ala31-Aib32. This motif has been shown to induce a 3(10)-helical turn in the region 28-31 of NPY and is suggested to be the key motif for high Y5-receptor selectivity. The results of feeding experiments in rats treated with the first highly specific Y5-receptor agonists support the hypothesis that this receptor plays a role in the NPY-induced stimulation of food intake. In conclusion, the selective compounds for the different Y receptor subtypes known so far are promising tools for a better understanding of the physiological properties of the hormones of the NPY family and related receptors.
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Affiliation(s)
- C Cabrele
- Department of Pharmacy, ETH Zurich, Switzerland
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Rawdon BB, Andrew A. Gut endocrine cells in birds: an overview, with particular reference to the chemistry of gut peptides and the distribution, ontogeny, embryonic origin and differentiation of the endocrine cells. PROGRESS IN HISTOCHEMISTRY AND CYTOCHEMISTRY 1999; 34:3-82. [PMID: 10546282 DOI: 10.1016/s0079-6336(99)80004-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
This review deals with gut endocrine cells in birds. It focuses on both morphological and developmental aspects of these cells, which were included members of Pearse's APUD series. They comprise many cell types, which, in birds as in mammals, produce serotonin and a range of regulatory peptides. The chemical structure of most avian gut peptides has been established. These peptides and their functions are outlined here. The types and distribution of avian gut endocrine cells are detailed and compared with the situation in mammals. In birds, ultrastructural work has been limited to certain types of gut endocrine cell and not as widely applied as in mammals. However, immunocytochemistry has found widespread application in studies on birds: the hatching chick and also the adult chicken and certain other species such as the quail and duck have been studied. Gut endocrine cells showing immunoreactivity for the following peptides/serotonin have been identified: somatostatin, pancreatic polypeptide (PP), peptide YY, glucagon, secretin, vasoactive intestinal peptide, gastrin, cholecystokinin (CCK), neurotensin, motilin, gastrin-releasing peptide, substance P, enkephalin and serotonin. The colocalization of different peptides (including chromogranins) and of peptides and serotonin in the same gut endocrine cells is reviewed: notable amongst such associations are glucagon with PP and gastrin/CCK with neurotensin in the same cells. On morphological grounds cells have been identified as endocrine in avian gut from at least 9 days of incubation. Immunocytochemical studies show the majority of the various types first to appear between 12 to 14 days of incubation, with substantial numbers being recorded from 17 days onwards. Experimental studies on chicken and quail embryos have determined the embryonic origin of gut endocrine cells: evidence is unequivocal that such cells arise from the endoderm, not the neural crest, other ectoderm or the mesoderm. Studies on avian embryos have also contributed to our knowledge of mechanisms controlling the differentiation of gut endocrine cells: evidence shows that gut mesenchyme plays an important role in provoking (or inhibiting) the development of gut endocrine cells and there are indications that the endocrine cell pattern in gut is established early and that an axially-derived factor may be important in this process. The kinds of genetic mechanism possibly involved are mentioned but full elucidation of the processes concerned is awaited. A better understanding of the formation of endocrine tumours of the gut should result from the findings.
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Affiliation(s)
- B B Rawdon
- Department of Anatomy and Cell Biology, Faculty of Health Sciences, University of Cape Town, Observatory, South Africa.
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Coles BA, Croom WJ, Brake J, Daniel LR, Christensen VL, Phelps CP, Gore A, Taylor IL. In ovo peptide YY administration improves growth and feed conversion ratios in week-old broiler chicks. Poult Sci 1999; 78:1320-2. [PMID: 10515365 DOI: 10.1093/ps/78.9.1320] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The effects of in ovo Peptide YY (PYY) administration on growth and feed conversion ratios in a commercial broiler line were investigated. Six hundred Ross male x Cobb female eggs were administered either 0.9% saline (control) or 600 microg/kg egg weight PYY in ovo at Day 18 of incubation. On day of hatching, 210 birds from each treatment group were randomly placed by sex into pens. Body weights at placement were not different between treatment groups. Average chick body weight and adjusted pen feed conversion ratios were improved by PYY in ovo treatment at 7 d posthatch (165.7 vs. 170.2 g, P<0.02; and 1.55 vs. 1.49, P<0.04, respectively). No significant differences between treatments were noted for these parameters at 21 or 42 d of age. These results suggest that in ovo treatment of broiler chicken eggs with gastrointestinal hormones that increase intestinal nutrient absorption, such as PYY, may enhance chick performance.
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Affiliation(s)
- B A Coles
- Department of Poultry Science, North Carolina State University, Raleigh 27695-7608, USA
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Breen CM, Mannon PJ, Benjamin BA. Peptide YY inhibits vasopressin-stimulated chloride secretion in inner medullary collecting duct cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 275:F452-7. [PMID: 9729520 DOI: 10.1152/ajprenal.1998.275.3.f452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
mIMCD-k2 cells are derived from the inner medullary collecting duct of a mouse and exhibit electrogenic sodium absorption and cAMP- and vasopressin (AVP)-stimulated electrogenic chloride secretion [N. L. Kizer, B. Lewis, and B. A. Stanton. Am. J. Physiol. 268 (Renal Fluid Electrolyte Physiol. 37): F347-F355, 1995; and N. L. Kizer, D. Vandorpe, B. Lewis, B. Bunting, J. Russell, and B. A. Stanton. Am. J. Physiol. 268 (Renal Fluid Electrolyte Physiol. 37): F854-F861, 1995]. The purpose of the present study was to determine how peptide YY (PYY) affects electrogenic Na+ and Cl- current in mIMCD-k2 cells. Short-circuit currents (Isc) were measured across monolayers of mIMCD-k2 cells mounted in Ussing-type chambers. PYY did not alter baseline Isc, nor did it alter Isc in chloride-free conditions, indicating no effect on electrogenic sodium transport. Baseline chloride current in these cells is low; therefore, chloride short-circuit current (IClsc) was stimulated with AVP (10 nM) added to the basolateral surface and 10 microM amiloride added to the apical surface. Although apical applications of PYY had no effect, basolateral application of PYY caused attenuation of IClsc, with the maximal inhibitory dose (100 nM) causing 52 +/- 1.3% inhibition (IC50 = 0.11 nM). Inhibition by PYY of IClsc is mediated through the Y2 receptor subtype, as PYY-(3-36) was the only PYY analog tested that caused inhibition and was equipotent to PYY. Inhibition by PYY of IClsc was abolished following incubation with pertussis toxin. We also show that PYY inhibits AVP-stimulated cAMP accumulation, with a maximal inhibitory dose (100 nM) causing a 38% +/- 6% inhibition (IC50 = 0.16 nM), comparable to inhibition by PYY of IClsc. We conclude that PYY acts through either Gi or Go to inhibit adenylate cyclase activity, leading to a decrease in AVP-stimulated chloride current.
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Affiliation(s)
- C M Breen
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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McDonald TJ, Wang YF, Mao YK, Broad RM, Cook MA, Daniel EE. PYY: a neuropeptide in the canine enteric nervous system. REGULATORY PEPTIDES 1993; 44:33-48. [PMID: 8484018 DOI: 10.1016/0167-0115(93)90128-u] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This study re-examined the anatomical locations of PYY in the canine gastrointestinal tract. Immunohistochemical studies with two relatively selective PYY antisera demonstrated PYY-LI immunoreactivity in nerve cell bodies and nerve fibres in the intestinal and gastric myenteric plexus and the intestinal submucosal plexus and in nerve fibres of the intestinal deep muscular plexus. Immunoreactive PYY-LI was also present in ileal endocrine cells. All PYY-LI immunoreactivity was completely abolished by pre-incubation of the antibodies with synthetic PYY but was unaltered by pre-incubation with synthetic NPY. Individual synaptosomal preparations obtained from canine intestinal and gastric myenteric plexus, and intestinal deep muscular plexus and submucous plexus, contained considerable quantities of PYY-LI which, on reverse-phase HPLC, co-eluted with a synthetic canine/porcine PYY standard. In contrast, isolated myenteric ganglia from rat and guinea pig did not contain detectable amounts of PYY-LI. These studies demonstrate that PYY is not confined to distal intestinal endocrine cells in the dog but is also an enteric neuropeptide with maximal concentrations being present in the intestinal myenteric plexus.
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Affiliation(s)
- T J McDonald
- Department of Medicine, University of Western Ontario, London, Canada
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Gastrointestinal Peptide Binding and Function in the Brain: Emphasis on Peptide YY. NEUROENDOCRINE PERSPECTIVES 1990. [DOI: 10.1007/978-1-4612-3446-3_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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17
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Taylor IL. Pancreatic Polypeptide Family: Pancreatic Polypeptide, Neuropeptide Y, and Peptide YY. Compr Physiol 1989. [DOI: 10.1002/cphy.cp060221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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18
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19
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Dockray GJ. Comparative Neuroendocrinology of Gut Peptides. Compr Physiol 1989. [DOI: 10.1002/cphy.cp060208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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20
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Nilsson S, Holmgren S. Novel neurotransmitters in the autonomic nervous systems of nonmammalian vertebrates. Pharmacol Ther 1989; 41:257-87. [PMID: 2565580 DOI: 10.1016/0163-7258(89)90110-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- S Nilsson
- Department of Zoophysiology, University of Göteborg, Sweden
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21
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Tatemoto K, Nakano I, Makk G, Angwin P, Mann M, Schilling J, Go VL. Isolation and primary structure of human peptide YY. Biochem Biophys Res Commun 1988; 157:713-7. [PMID: 3202875 DOI: 10.1016/s0006-291x(88)80308-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The isolation, primary structure and chemical synthesis of human peptide YY (PYY) are described. The peptide was purified from human colonic extracts using a chemical method which detected the C-terminal tyrosine amide structure of PYY. Human PYY consists of 36 amino acid residues and the complete amino acid sequence is: Tyr-Pro-Ile-Lys-Pro-Glu-Ala-Pro-Gly-Glu- Asp-Ala-Ser-Pro-Glu-Glu-Leu-Asn-Arg-Tyr-Tyr-Ala-Ser-Leu-Arg-His-Tyr-Leu- Asn-Leu-Val-Thr-Arg-Gln-Arg-Tyr-NH2. The differences between the structures of porcine and human PYY are at positions 3 (Ala/Ile replacement) and 18 (Ser/Asn). Synthetic human PYY prepared using a solid-phase synthetic technique was found to be structurally identical to the natural peptide.
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Affiliation(s)
- K Tatemoto
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, California
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22
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Evolutionary Aspects of Gastrointestinal Hormones. ACTA ACUST UNITED AC 1988. [DOI: 10.1016/b978-0-12-027311-9.50007-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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23
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el-Salhy M, Grimelius L, Emson PC, Falkmer S. Polypeptide YY- and neuropeptide Y-immunoreactive cells and nerves in the endocrine and exocrine pancreas of some vertebrates: an onto- and phylogenetic study. THE HISTOCHEMICAL JOURNAL 1987; 19:111-7. [PMID: 3294760 DOI: 10.1007/bf01682755] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The occurrence of polypeptide YY- and neuropeptide Y-immunoreactive cells and nerves in the pancreas of some species from all the eight main vertebrate groups (cyclostomes, cartilaginous fish, bony fish, amphibia, reptiles, birds, and mammals) was investigated. In addition, an ontogenetic study of these neurohormonal peptides was performed, using the rat pancreas. The distribution of these two peptides was compared with that of the structurally closely related pancreatic polypeptide. Polypeptide YY-immunoreactive cells were found to occur in the endocrine pancreas and neuropeptide Y-immunoreactivity was observed both in neurons and nerve fibres. The polypeptide YY-immunoreactive cells were limited to mammals and reptiles only. Neuropeptide Y-immunoreactive neurons and nerves were observed in reptiles, birds, and mammals only. One reptilian species (out of three) and one mammalian (out of six) failed to show any kind of immunoreactivity for the polypeptide or neuropeptide. Pancreatic polypeptide-immunoreactive cells were found in all the species examined except in the hagfish islet. In rat foetuses, polypeptide YY-immunoreactive cells and neuropeptide Y-immunoreactive nerve elements were first demonstrated at the seventeenth day of gestation, whereas pancreatic peptide-immunoreactive cells did not appear until postnatally, namely in two day-old rats. The polypeptide-containing cells, a new cell type in the endocrine pancreas, are rare. In contrast to the pancreatic peptide cells, they do not seem to have any kind of regional distribution.
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24
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Barbosa AJ, Nogueira JC, Penna FJ, Polak JM. Distribution of enteroglucagon- and polypeptide YY-immunoreactive cells in the gastrointestinal tract of the white-belly opossum (Didelphis albiventris). HISTOCHEMISTRY 1987; 88:37-40. [PMID: 3325477 DOI: 10.1007/bf00490164] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Several segments of the gastrointestinal tract of the white-belly opossum Didelphis albiventris were investigated immunocytochemically for the occurrence of polypeptide YY (PYY) and enteroglucagon (GLU). PYY- and GLU-immunoreactive cells were observed in the lower part of the ileum, cecum and colon. These cells were seen to emit cytoplasmic basal processes to the neighbouring cells with a number of them reaching the glandular lumen via apical cytoplasmic process. GLU-immunoreactive cells were also present in the oxyntic mucosae and in the pancreatic duct. Staining of consecutive sections for the two polypeptides, respectively, revealed the coexistence of immunoreactivity for PYY and GLU in the same cell type.
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Affiliation(s)
- A J Barbosa
- Department of Pathology, Universidade Federal de Minas Gerais, Belo Horizonte, Brasil
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25
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Böttcher G, Alumets J, Håkanson R, Sundler F. Co-existence of glicentin and peptide YY in colorectal L-cells in cat and man. An electron microscopic study. REGULATORY PEPTIDES 1986; 13:283-91. [PMID: 3754646 DOI: 10.1016/0167-0115(86)90046-7] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Electron microscopic immunocytochemistry using protein A-gold labelling of ultrathin sections revealed immunoreactive glicentin (gut-type glucagon) and peptide YY (PYY) in virtually all secretory granules in a population of L-type endocrine cells in feline colon and human rectum. The granules of the human glicentin/PYY cells were considerably smaller in size than those in the cat. In both species the results indicate co-existence of glicentin and PYY in the same secretory granules, despite the probable derivation of the two peptides from two different precursors.
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26
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Böttcher G, Skagerberg G, Ekman R, Håkanson R, Sundler F. PYY-like peptides in the central and peripheral nervous system of a frog and a lizard. Peptides 1985; 6 Suppl 3:215-21. [PMID: 3913906 DOI: 10.1016/0196-9781(85)90377-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
PYY-immunoreactive material was detected in endocrine cells in the gut of a lizard, Lacerta vivipara, and a frog, Rana temporaria. The findings are consistent with other reports on reptiles, amphibians and higher species. In addition, however, PYY-like material was found in neuronal elements both in the gut and in the brain. High performance liquid chromatography of frog brain extracts showed the PYY-like material to elute in one minor fraction (eluting position similar but not identical to that of porcine synthetic PYY) and two major fractions (distinct from PYY and probably representing smaller and more hydrophobic PYY-like peptides).
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27
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Rawdon BB. Gastrointestinal hormones in birds: morphological, chemical, and developmental aspects. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1984; 232:659-70. [PMID: 6084044 DOI: 10.1002/jez.1402320335] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Historically, the enterochromaffin cell was the first endocrine cell type detected in avian gut; subsequently, a number of types of such cells were distinguished on the basis of the ultrastructural features of the secretory granules. More recently, immunocytochemical procedures have revealed somatostatin-, pancreatic polypeptide (PP)-, polypeptide YY-, glucagon-, secretin-, vasoactive intestinal peptide (VIP)-, gastrin-, cholecystokinin-, neurotensin-, bombesin-, substance P-, enkephalin-, motilin-, and FMRFamide-like immunoreactivity in avian gastrointestinal endocrine cells. Most endocrine cells are located in the antrum; there are a number in the proventriculus and small intestine but few in the gizzard, cecum, and rectum. Several avian gastroenteropancreatic hormones, including glucagon, VIP, secretin, bombesin, neurotensin, and PP, have been isolated and sequenced. They resemble the equivalent mammalian peptides in terms of molecular size but differ in amino acid composition and sequence; some (e.g., VIP) differ only in minor respects, others (e.g., secretin) more radically. Gastrointestinal endocrine cells appear late in development; available data indicate that few types are recognized by either immunocytochemistry or electron microscopy before 16 days of incubation. Experimental evidence has shown that at least the majority of gut endocrine cells are of endodermal origin and are not derived from the neural crest or neuroectoderm as earlier proposed. In early embryos, the progenitors of gastrointestinal endocrine cells are more widespread than are the differentiated cells in chicks at hatching. This, along with other observations, raises the question of factors that might influence the differentiation of gut endocrine cells.
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28
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Ali-Rachedi A, Varndell IM, Adrian TE, Gapp DA, Van Noorden S, Bloom SR, Polak JM. Peptide YY (PYY) immunoreactivity is co-stored with glucagon-related immunoreactants in endocrine cells of the gut and pancreas. HISTOCHEMISTRY 1984; 80:487-91. [PMID: 6384152 DOI: 10.1007/bf00495439] [Citation(s) in RCA: 174] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In this study we report the localisation of PYY immunoreactivity in intestinal mucosa endocrine (EG) cells containing glucagon-related peptides and also in foetal pancreatic A cells of rat and man. Radioimmunoassay of human foetal pancreatic extracts revealed the presence of PYY immunoreactivity, the concentration of which declined with age (from 65.42 pmol/g at week 20 to 17.0 pmol at week 40; correlation coefficient = -0.893), in contrast to the amount of glucagon which remained statistically constant throughout the same foetal period. The identity of this PYY immunoreactive material with the original 36 amino acid porcine peptide has been shown by high pressure liquid chromatography (HPLC).
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29
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Rombout JH, Reinecke M. Immunohistochemical localization of (neuro)peptide hormones in endocrine cells and nerves of the gut of a stomachless teleost fish, Barbus conchonius (Cyprinidae). Cell Tissue Res 1984; 237:57-65. [PMID: 6206950 DOI: 10.1007/bf00229200] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Enteroendocrine cells containing glucagon-, substance P-, neurotensin- and VIP-like substances have been demonstrated immunocytochemically in the gut of Barbus conchonius. Mainly based on the distribution of the immunoreactive endocrine cells in this and a previous study, at least eight different enteroendocrine cell types appear to be present in this stomachless fish: C-terminal-gastrin-immunoreactive cells, predominantly present in the upper parts of the folds of the proximal part of the intestinal bulb. Metenkephalin-immunoreactive cells, basally located in the folds of the first segment. Pancreatic polypeptide (PP)-immunoreactive cells, mainly present in the first half of the first segment. Glucagon-like-immunoreactive (GLI) cells that are basally located in the folds of the first segment and that contain a different polypeptide (possibly glicentin) than pancreatic glucagon cells. Substance P-immunoreactive cells, present in the upper parts of the folds throughout the gut. C-terminal-neurotensin-immunoreactive cells, basally located in the folds throughout the first segment. Vasoactive intestinal polypeptide (VIP)-immunoreactive cells, present in small numbers in the proximal part of the intestinal bulb. Nonspecifically-immunoreactive cells, found throughout the intestinal bulb. Many VIP-immunoreactive nerves have been demonstrated in the smooth muscle layer and myenteric plexus of the gut; furthermore some of them are peptide histidine-isoleucine (PHI)-immunoreactive. Substance P-, somatostatin-, neurotensin- and met-enkephalin-immunoreactive nerves are also found. Thus, at least partial sequences of four different mammalian neuropeptide hormones (VIP, substance P, neurotensin, met-enkephalin) occur both in endocrine cells and enteric nerves of the gut of B. conchonius.
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30
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EL-SALHY MAGDY. Occurrence of polypeptide YY (PYY) and pancreatic polypeptide (PP) in the gastrointestinal tract of the bony fish . Biomed Res 1984. [DOI: 10.2220/biomedres.5.441] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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31
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Wilander E, El-Salhy M, Lundqvist M, Grimelius L, Terenius L, Lundberg JM, Tatemoto K, Schwartz TW. Polypeptide YY (PYY) and pancreatic polypeptide (PP) in rectal carcinoids. An immunocytochemical study. VIRCHOWS ARCHIV. A, PATHOLOGICAL ANATOMY AND HISTOPATHOLOGY 1983; 401:67-72. [PMID: 6412449 DOI: 10.1007/bf00644790] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The frequency and distribution of polypeptide YY (PYY) and pancreatic polypeptide (PP) immunoreactive tumour cells of 14 small intestinal and of 27 rectal carcinoids were studied. All small intestinal and 14 rectal tumours were unreactive to both hormones. However, 13 rectal carcinoids contained a variable number of PP-immunoreactive cells. In four of these cases both PYY- and PP-immunoreactive cells were seen. The PP-immunoreactive cells greatly exceeded the number of PYY-immunoreactive cells. Two rectal carcinoids with PYY and PP immunoreactivities, but not the rest of the tumours, reacted also with an antiserum specific to the C-terminus of PP. This indicates that most PP immunoreactive rectal carcinoids lack the C-terminus sequence of the PP molecule.
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32
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El-Salhy M, Wilander E, Juntti-Berggren L, Grimelius L. The distribution and ontogeny of polypeptide YY (PYY)- and pancreatic polypeptide (PP)-immunoreactive cells in the gastrointestinal tract of rat. HISTOCHEMISTRY 1983; 78:53-60. [PMID: 6347987 DOI: 10.1007/bf00491111] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The distribution and ontogeny of polypeptide YY (PYY)- and pancreatic polypeptide (PP)-immunoreactive cells in the gastrointestinal tract of rat were investigated. PYY-immunoreactive cells were numerous in the pylorus, ileum and colon and only a few cells were observed in the corpus, duodenum, jejunum and rectum. On the other hand, a few PP-immunoreactive cells were seen in the colon only. Both PYY- and PP-immunoreactive cells were of the open type, i.e., they extended from the basal lamina to the gut lumen. PYY-immunoreactive cells were observed first in the lower half of the stomach and in the intestine of 19 day-old embryo. The localization of the cells seemed to move along towards the pylorus and the lower part of the intestine. PP-immunoreactive cells could only be detected for the first time in the colon of 2 day-old rat. These cells appeared temporarily in the pylorus and rectum during the period 7 to 21 days after birth. It was concluded that the difference between PYY- and PP-immunoreactive cells in the distribution, frequency and ontogeny provide further evidence that PYY and PP occur in two independent cell types.
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